Note (20) — BOOK VII.
James Greive translation
20. Two regulæ.) Regula is commonly taken for a ruler. Our author himself directs a single regula to be applied to a fractured bone, where there is a protuberance, to keep that down, Lib. viii. cap. 10. In this place he mentions the end proposed by them. It seems probable that they were two pieces of wood fixed together by a hinge, and used in the same manner as farriers use the instrument by them called barnacles.